Remove my wifes ex husband from a deed

my wife's first marriage lasted about 12 years. she and her 1st husband purchased a home with both there names on the loan/deed. he left her and the 3 kids in 2000. unable to handle the mortgage payments my wife filed for bankruptcy (i didn't find this out until after we were married). she waited 2 years to file for divorce because she didn't have the money and filed the cheapest way possible, because he had left 2 years ago he wasn't required to even sign. the divorce decree make no mention of the house. we were married 3 years ago and last year the bankruptcy payment amount was adjusted. once i found out, about the bankruptcy i gifted her the money (about 12k) to pay it off in full. the house her car and an old home equity loan were included in the payoff. i have never pushed the issue with my wife about the house, until now.... her alcoholic, out of work ex has been tossed out by his girlfriend and he claims he wants me out and he is going to move back in..... here's the question. since the house has been paid off (about a year ago) what steps do we need to take to get the ex off of the deed. there is no chance that he will be willing to co-operate and sign anything. i had always hoped we wouldn't have any problems until we went to sell the house but things aren't working my way. i have also put about 25k into the property (new roof windows, etc.) which i figured would work to our advantage when we sold if he tried to sue for half the proceeds. is there any way to remove his name/add mine without him having to sign since he abandon the property 7 years ago? can my name be added without him having to sign since i have so much invested in the house? or is this just going to get real ugly when try to sell (in 2 years, we hope)
we live in pa and have not rcv'd a deed yet from the attorney that handled the banruptcy. (not sure if that comes from the attorney or the bank) we just got the title for the car about a month ago.

any advise would be appreciated......